Road barriers of the wall kind and having a New Jersey (NJ) profile, which are made of monolithic blocks of concrete and which, after their assembling, give rise to a high quality protection, are already known in the art. In those barriers the calibration of the deceleration is obtained, in case of motorcars and generally of light vehicles, by means of the lifting of the vehicle due to the New Jersey shape, and at the same time, due to the presence of sliding shoes, if any, which facilitate the displacement of the barrier and which are interposed between the barrier and its support. Therefore, if the impact angle is restricted, the motorcar is again deviated towards the carriageway, whereas, if it is noticeable, the sliding shoes will promote the displacement of the barrier and calibrate the deceleration values, as mentioned above.
The barriers of the wall type, even if provided with slide facilitating devices (shoes) acting during part of the maximum allowable displacement, as disclosed in some patent applications of the same applicant, and even if provided with a projecting socle (base) having a New Jersey profile or a different configuration, always give rise to a deceleration caused by the collision, and to relevant components of the same in the longitudinal, transversal, and vertical direction with respect to the direction of motion.
In particular, the vertical component is very strong for those types of barriers, and also the transversal component is usually of an impulsive nature (the longitudinal component is more distributed in time). The first of these components has a beneficial effect on the dissipation of kinetic energy of motorcars, since it converts the same into potential energy (lifting), which will be returned after some time, but its generation must not occur simultaneously to that of the transversal impulsive component, because otherwise both components contribute simultaneously to the amount of acceleration given by the ASI (Acceleration Severity Index), the latter being used during type approval tests for the evaluation of the maximum admissible energy to which the passengers of the motorcar may be subjected, under standard extreme conditions of type tests for road barriers.
“U.S. Pat. No. 4,681,302 discloses a barrier for dissipating kinetic energy upon impact by a moving vehicle. The barrier modules may be filled with water to increase their weight and they are resiliently deformable to return to their original shape after being struck.
The barrier disclosed in this document, may form a traffic divider and it captures the vehicle tire, tending to slow the tire and preventing it from climbing and the vehicle from vaulting.
This kind of barrier includes also traction spoiler channels to reduce the area of contact between the barrier and the tires of a vehicle.
While this patent U.S. Pat. No. 4,681,302 already contains the idea of realising a deformable barrier, this barrier does not allow the wheel to climb, so as to convert part of the vehicle kinetic energy into potential energy. Moreover, this barrier is not resistant enough to be used as a “bivalent barrier”, that is a barrier stopping heavy vehicles as well as light vehicles.
Therefore, although it may be very useful in certain cases, it does not belong to the same category of barriers as those of the present invention, and consequently it does not achieve the objects of the present invention.”